Door construction and control mechanism



May 29, 1928. 1,671,608

' W. M. PRATT DOOR CONSTRUCTION AND CONTROL MECHANISM Filed Jan. 11, 1926 2.5haets-Sheet 1 May 29, 1928.

W. M. PRATT DOOR CONSTRUCTION AND CONTRQL IECHANISI 2 Sheets-Spout 2- Filed Jan. 11, 1926 aupenkm jfader/ilra 6t Patented May 29, 1928.

UNITED STATES WALTER M. PRATT, or BIRMINGHAM, MICHIGAN.

1300i CONSTRUCTIONAND CONTROL MECHANISM.

Application filed January 11, 1926. Serial no. 80.656.

This invention relates to door constructions and control mechanisms therefor, and particularly relates to doubleswinging doors and means for actuating such doors in unison. v 7 I It is an object of theinvention to mount a pair of swinging doors respectively at the upper and lower margins of adoorway, and to so proportion and control said doorsthat the upper will form a canopy over the lower, both in their fully opened positions and during their opening or closing travel.

Another objectis to provide a pair of doors hinged respectively at the upper and lower margins of a doorway, and a stop member encountered by one of said doors as they approach their closed positions, which member must be manually released before the doors may fully close.

A further object is to provide a control mechanism for a pair of swinging doors con trolling an entrance to a building, which mechanism is operable interiorly of the building doors. A still further object is to provide a mechanism establishing unitary control over a pair of swinging doors, and comprising a member similarly actuable to open or close the doors. i

It isalso an object of the invention to hinge a pair of doors upon opposed margins of a door opening,, and to pro'videa connection between said doors for subjecting them to acomino'n control which mechanism will act to automatically lock both doorsin their opened positions;

Another object is to so hinge a pair of garage doors to the upper and lower margins of a doorway that the impact of a vehicle upon one or both of said doors may be safely utilized to effect an opening movement of the doors.

Another object is to-provide a control mechanism for a pair of swinging doors that will comprise meansfor assisting the initial portion of both the opening and closing movement of the doors, andfor resisting the final portion of such movement.

, These and various other objects are attained bvthe construction hereinafter described and illustrated in the accompanying drawings, wherein:

Figure 1 is a View in interior elevation of the improved doors in theirclosed positions, and their control mechanism.

for either opening or closing said Figure 2 is a vertical sectional View of the doors taken upon the line 22 of Figure 1. Figure 3 is view similar to Figure 2, but showing an approximately mid position of the doors.

In these views the reference character 1 designates a door frame which may be part of a garage or any other building. A pair of doors 2 and 3 are hinged as indicated at 4: respectively to the top and bottom meni bers of said frame being thus adapted to swing outwardly from the closed position shown in full lines in Figure 2 to the dash line positions indicated in said figure. Preferably the edges 5 of said doors, remote from their hinges, are beveled to adapt the upper door to slightly overlap the lower one. in their closed positions. Also it is preferred to give the upper door a greater ex tent outwardly from its hinge axis than that of the lower door, so that when the doors are open or in any intermediate position, the upper one will adequately shield the lower from rain or snow.

To compel a movement of said doors in unison as they are opened or closed, and also to establish a counter-balancing relation, they are connected by a pair of swinging link bars 6 terminally pivoted to brackets 7 These brackets are spaced some distance from the hinges 4 to afford the bars (3 an adequate leverage in transmitting thrust. It is important to note that the extended lines of thrust of the bars 6 lie a shortdistance outwardly from the hinge axis of the lower door. This permits utilization of said bars as looking members to maintain the open positions of the doors. That to say when the doors are fully open, the thrust exerted by the upper one through the bars 6 upon the lower one resists to some extent any closing movement of the two doors. This locking action, however, may be overcome by slightly raising the lower (lOOI'ytllOlGbY shiftingthe thrust axis ofthe bars 6 in wardly of the hinge axis of said door.

Describing now the door control mechanism, 9 is a sheave journaled in a hanger 10 swivellv secured by a bolt 11 to the free end of a bracket member 12 projecting inwardly from the lintel 12 at oneside of the door opening. A' cable or the like 13 has one end connected through a coiled spring 14 to the. floor 15 of the building to which the doors 2 and 3 give access. Said cable passes over the sheave 9, and extends downwardly to engage a smaller sheave 16 journaled on a bracket member 17 projecting from a side of the frame, at substantially the meeting level of the doors in their closed positions. Said cable passes once around the sheave 16, and is then extended to the free end of an arm 18 projecting from one of the brackets 8, and is terminally secured to said arm.

Considering now the operation of the described control mechanism, it is to be understood that the spring 14 is under a predetermined maximum tension when the doors 2 and 3 are either fully opened or closed. To open or close the doors, the operator exerts a downward pull upon that portion of the cable 13 to which the spring 14-is connected,

maintaining such pull, however, only during travel of the doors to their approximate mid positions (see Fig. 3). ThlS pull is transmitted through the cable to the lower door and acts upon the upper door through the link bar6. It is to be noted that the pull thus applied is supplemented by the spring 14, the tension of which is fully relieved in said mid positions of the doors in which the free end of the arm 18 is in close proximity to the lower sheeve 16. The balance of the opening or closing movement of the doors is accomplished throughtheir momentum acquired during the described initial actuation. It will be evident that during opening of the doors, the upper one prevents a too sudden descent of the lower, and similarly the lower door causes retardation of the upper, during a. closing movement. The direction of travel of the cable 13 is reversed when the arm 18 travels past the sheave 16 so that during the final portion of either the opening or closing movement of the doors they are acting to tension the spring 14 and said portion of their travel is thus cushioned.

Upon one of the uprights of the door frame there is pivoted a stop bar 19 which, when the door is fully closed, is upwardly swung against a pin 20 as shown in dash lines in Fig. 2, so as to lie entirely within the door frame. As the doors are opened, said stop bar drops of its own weight to the position shown in full lines in Fig. 2, seating upon a pin 21 upon said upright. In this position said bar encounters the upper door 2 in a substantially transverse relation to the latter, as the two doors approach their closed ositions. thus preventing their com plete closing. Said stop bar must be manually swung to its raised position, before the doors may fully close, and thus acts as a safety device to prevent the operator or anyone else being pinched between the doors, as they close. Preferably thebar 19 projects sufficiently beyond its pivotal end to form a handle 19 which may be grasped in releasing said bar from its position of use.

Preferably a yieldable bumper is carried by the door 2 to engage the stop bar 19. In the illustrated embodiment of the invention this bumper has the form of a flexible strap 22 spaced slightly from the inner face of the door and anchored at one end directly to a block 23 upon the door while its other extremity is connected by a turn-buckle 24: to a bracket '25. Said turn-buckle permits taking up of slack in the strap 22 in case this becomes necessary after a period of use.

It is preferred to mount-upon the interior face of the lower door a pair of angular guard bars 26 which are respectiveliy; adacent to the brackets 8 between the tter, and which safeguard said brackets against damage by the wheels ofa vehicle traveling across said door. Said door is preferably of a stronger and heavier construction than the upper one since it is required to form a ramp or platform for a vehicle entering or leaving the garage (or other building). This relatively heavy construction furthermore compensates to a considerable extent for the greater area of the upper door, in

maintaining the desired counter-balanced.

relation of the two doors. The weight added to the lower door by the guard bars 26 is a further compensation for the relatively large area of the upper door.

A plurality of cleats 28, exteriorly secured to the lower doorstrongly reinforce said door, increase the weight of said door, as an additional compensation for the eater area of the up er door, and transmit t load acting on said door when a vehicle is crossing the same, directly to the pavement.

The utilization of the lower door in its open position as a canopy preventing any accumulation of rain or snow upon the lower door is of importance, since such accumulation would otherwise be deposited on the floor 15 of the garage (or other building) upon closing of the doors.

Employment of the door 3 in its open position as an inclined platform permits the floor of a. garage (or other building) to be raised above the level of the pavement (or grade) forming an approach to the doorway, than would otherwise be practicable, and thus decreases the possibilit ofwater entering across the threshold 0 the door- 'wav.

The operation of the described control mechanism is simplified by the fact that bot-h the opening and closing movement of the doors is accomplished by exerting the same pull upon the cable 13.

Any suitable means may be provided for fastening the two doors in their closed positions, as for example, an ordinary turn button 27 pivoted interiorly upon one of the doors adjacent its free edge and engagegble with the free edge portion ofthe other oor.

i 1,e71,eos

Because of the described counter-balancing of the doors and in view of the cushioning effect of the spring 14, it is feasible to open the above doors if desired by the impact of a vehicle against the inner faces of either or both doors. Vithout the retardation due to said counter-balanced relation and to the spring, the vehicle impact would be likely to move the doors too violently.

WVhat I claim is:

1 In a door construction, a door frame forming a doorway, a pair of outwardly swinging doors hinged respectively to the upper and lower edges of said frame, and jointly closing said doorway in their closed positions, and a link bar forming a swinging connection between said doors adapting them for actuation in unison, the axis of said bar in the fully opened positions both of said doors lying outwardly of the hinge axis of the lower door, adapting said bar to form a locking member for maintaining said positions. j

2. In a door construction, the combination with a door frame, and a door hinged to the upper margin of said frame, of a door stop for positively holding the door partially open, movable between a position of use and a position of disuse, and manually releasable from its position of use, and a member engageable by said stop in its position of use for positively maintaining said (position under impact of the door.

3. In a door construction, the combination with a door frame, and a door hinged to the upper margin of said frame, of a door stop for positively holding the door partially open, mounted upon the said frame, and movable between a position of use and a position of disuse, and a member carried by the frame engageable by said stop in its position of use for positively maintaining said position under impact of the door.

4. A door construction comprising a door frame, a door hinged at the upper margin of said frame, and a door stop pivoted upon said frame and manually adjustable pivotally from a lowered position of engagement with said door in a partially closed position of the latter to a raised stored position substantially within said frame, and gravityactuable from its. raised to its. lowered position.

5. A door construction comprising a door frame, a door hinged at the upper margin of said frame, a stop member mounted upon said frame, engageable by said door in a partially closed osition thereof, and adjustable upon said rame to permit full closing of the door, and a yieldable bumper upon the door forming a seat to engage said stop member. j

6. A door, comprisinga pair of swinging doors hinged respectively at the upper and lower margins of a doorway, meanscona door stop for holding said doorspartially open, engageable in its position of use by one of said doors and movable to a POSltlOIl of disuse, and means co-acting with said stop in its position of use to positively maintain said position under impact of the engaging door.

7. The combination with a door frame, and a door hingedly mounted in said frame, of a stop bar pivoted upon said frame, engageable at one side of its pivot with the door, to hold said door partially open and projecting beyond its pivot at the other side thereof, to form a handle and actuable by said handle from its door engaging position to a. position of disuse.

8. In a door construction, a pair of swinging doors hinged respectively to opposite margins of a doorway, a connection between said doors compelling opening and closing thereof in unison, an actuating member for the doors, and means connected to said actuating member retarding the final portion of the opening and closing movement of the doors.

9. In a door construction, a pair of swinging doors hinged respectively at op posite margins of a doorway, a connection between said doors compelling opening and closing travel thereof in unison, a cable engaged at one extremity with one of said doors for effecting an initial opening or closing actuation of the doors, and means connected to said cable resisting the final portion of opening or closing travel of the doors.

10. In a door construction, a pair of swing doors hinged respectively at the upper and lower margins of a doorway, means connecting said doors compelling opening and closing travel thereof in unison, a cable connected to the lower door for opening and closing the doors, a sheave over which said cable is carried approached by the point of connection. of the cable to the lower door in an approximate mid position of the doors, and a yieldable member anchoring the other extremity of said cable.

11. In a door construction, a pair of swinging doors hinged respectively at the upper and lower margins of a doorway, means connecting said doors for actuation in unison, a flexiblemember engaging one of said doors for actuating both doors, a sheave over which said cable is carried approached by the door engaging end of the cable during the initial poition of both the opening and closing movement of the doors, and means yieldably anchoring the other end of said cable.

12. In a door construction, a door, means hingedly mounting said door, a member exercising a primary control of said door and closing movement, and a spring anchoring the other endof said cable, adapted to retard the final portion of the opening and closing movement of the door.

In testimony whereof I sign this specification.

WALTER M. PRATT. 

